Least-cost Disjoint Paths with Dependent Cost Structure in Wavelength Continuous Optical WDM Networks

One of the important issues in establishing a fault tolerant connection in a wavelength division multiplexing optical network is computing a pair of disjoint working and protection paths and a free wavelength along the paths. While most of the earlier research focused only on computing disjoint paths, in this work we consider computing both disjoint paths and a free wavelength along the paths. The concept of dependent cost structure (DCS) of protection paths to enhance their resource sharing ability was proposed in our earlier work. In this work we extend the concept of DCS of protection paths to wavelength continuous networks. We formalize the problem of computing disjoint paths with DCS in wavelength continuous networks and prove that it is NP-complete. We present an iterative heuristic that uses a layered graph model to compute disjoint paths with DCS and identify a free wavelength.

Taking account of dependent species in management of the Southern Ocean krill fishery: estimating crabeater seal abundance off east Antarctica

1. The crabeater seal Lobodon carcinophaga is considered to be a key species in the krill-based food web of the Southern Ocean. Reliable estimates of the abundance of this species are necessary to allow the development of multispecies, predator–prey models as a basis for management of the krill fishery in the Southern Ocean. 2. A survey of crabeater seal abundance was undertaken in 1500 000 km2 of pack-ice off east Antarctica between longitudes 64–150° E during the austral summer of 1999/2000. Sighting surveys, using double observer line transect methods, were conducted from an icebreaker and two helicopters to estimate the density of seals hauled out on the ice in survey strips. Satellite-linked dive recorders were deployed on a sample of seals to estimate the probability of seals being hauled out on the ice at the times of day when sighting surveys were conducted. Model-based inference, involving fitting a density surface, was used to infer densities in the entire survey region from estimates in the surveyed areas. 3. Crabeater seal abundance was estimated to be between 0.7 and 1.4 million animals (with 95% confidence), with the most likely estimate slightly less than 1 million. 4. Synthesis and applications. The estimation of crabeater seal abundance in Convention for the Conservation of Antarctic Marine Living Resources (CCAMLR) management areas off east Antarctic where krill biomass has also been estimated recently provides the data necessary to begin extending from single-species to multispecies management of the krill fishery. Incorporation of all major sources of uncertainty allows a precautionary interpretation of crabeater abundance and demand for krill in keeping with CCAMLR’s precautionary approach to management. While this study focuses on the crabeater seal and management of living resources in the Southern Ocean, it has also led to technical and theoretical developments in survey methodology that have widespread potential application in ecological and resource management studies, and will contribute to a more fundamental understanding of the structure and function of the Southern Ocean ecosystem.

IANR Recognition Luncheon

What a pleasure it is to come together here to recognize and celebrate Outstanding work of members of our IANR community. It is even more of a treat to have three reasons to celebrate today as we recognize excellence with two IANR Exemplary Service Awards, two Dinsdale Family Faculty Awards, and the IANR Team Award.

Holocarboxylase Synthetase-dependent Biotinylation of Histone H4

Holocarboxylase synthetase (HCS) catalyzes the binding of biotin to lysine (K) residues in histones H3 and H4. Histone biotinylation marks play important roles in the repression of genes and retrotransposons. Preliminary studies suggested that K16 in histone H4 is a target for biotinylation by HCS. Here we demonstrated that H4K16bio is overrepresented in repeat regions {pericentromeric alpha satellite repeats; long terminal repeats (LTR)} compared with euchromatin promoters. H4K16bio was also enriched in the repressed interleukin-2 gene promoter. The enrichment at LTR22 and promoter 1 of the sodium-dependent multivitamin transporter (SMVT) depended on biotin supply; and was significantly lower in fibroblasts from an HCS-deficient patient compared with an HCS wild-type control. We conclude that H4K16bio is a real phenomenon and plays a role in the transcriptional repression of repeats and genes. HCS catalyzes the covalent binding of biotin to carboxylases, in addition to its role as a histone biotinyl ligase. HCS null individuals are not viable whereas HCS deficiency is linked to developmental delays and phenotypes such as short life span and low stress resistance. Here, we developed a 96-well plate assay for high-throughput analysis of HCS based on the detection of biotinylated p67 using IRDye-streptavidin and infrared spectroscopy. We demonstrated that the catalytic activity of rHCS depends on temperature and time, and proposed optimal substrate and enzyme concentrations to ensure ideal measurement of rHCS activity and its kinetics. Additionally, we demonstrated that this assay is sensitive enough to detect biotinylation of p67 by endogenous HCS from Jurkat lymphoid cells.

IANR Recognition Luncheon, Dinsdale Family Faculty Awards, and IANR Team Award Presentations

What a pleasure it is to come together to recognize and celebrate Outstanding work of members of our IANR community. Today we celebrate excellence as we present two Dinsdale Family Faculty Awards, as well as our IANR Team Award.

Sexual Risk Recognition Deficits: The Role of Prior Victimization and Emotion Dysregulation

Recent theoretical writings suggest that the ineffective regulation of negative emotional states may reduce the ability of women to detect and respond effectively to situational and interpersonal factors that increase risk for sexual assault. However, little empirical research has explored this hypothesis. In the present study, it was hypothesized that prior sexual victimization and negative mood state would each independently predict poor risk recognition and less effective defensive actions in response to an analogue sexual assault vignette. Further, these variables were expected to interact to produce particularly impaired risk responses. Finally, that the in vivo emotion regulation strategy of suppression and corresponding cognitive resource usage (operationalized as memory impairment for the vignette) were hypothesized to mediate these associations. Participants were 668 female undergraduate students who were randomly assigned to receive a negative or neutral film mood induction followed by an audiotaped dating interaction during which they were instructed to indicate when the man had “gone too far” and describe an adaptive response to the situation. Approximately 33.5% of the sample reported a single victimization and 10% reported revictimization. Hypotheses were largely unsupported as sexual victimization history, mood condition, and their interaction did not impact risk recognition or adaptive responding. However, in vivo emotional suppression and cognitive resource usage were shown to predict delayed risk recognition only. Findings suggest that contrary to hypotheses, negative mood (as induced here) may not relate to risk recognition and response impairments. However, it may be important for victimization prevention programs that focus on risk perception to address possible underlying issues with emotional suppression and limited cognitive resources to improve risk perception abilities. Limitations and future directions are discussed.

Nebraska Bankers scholarship Recognition Dinner

Good evening. It is indeed a pleasure to be part of this very first Nebraska Bankers Scholarship Recognition Dinner. My heartiest congratulations to each of our 20 student recipients of the 2007-2008 Nebraska-Bankers Scholarship Program. I know I speak for everyone in this room when I say we look forward with great enthusiasm to the great work you will do, after you graduation, to the important contributions you will make in your chosen field and the communities you will serve over your careers.

FOREST ANIMAL DAMAGE CONTROL

As a nation we have gained world recognition for our ability to utilize our resources. In forestry our greatest accomplishments have been in the mechanization of harvest methods and in improvements in forest products. The renewal of this resource has been our greatest neglect. Though the end of the 19th Century marked the beginning of the conservation movement, it was not until a half century later that the force of economics through the demands of a growing population made forest re-establishment more than just a desire. Conservation in itself is a Utopian concept which requires other motivating forces to make it a reality. In the post-war years, and as late as the early 195O's, stocked land in the Pacific Northwest could be purchased for less than the cost of planting; the economic incentive was lacking. Only with sustained yield management and increased land values was there a balance in favor of true values. With greater effort placed on forest regeneration there was an increased need for methods of reducing losses to wildlife. The history of forest wildlife damage research, therefore, parallels that of forest land management; after rather austere beginnings, development became predominantly a response to economics. It was not until 1950 that the full time of one scientist was assigned to this important activity. The development of control methods for forest animal damage is a relatively new area of research. All animal life is dependent upon plants for its existence; forest wildlife is no exception. The removal of seed and foliage of undesirable plants often benefits the land managers; only when the losses or injuries are in conflict with man's interest is there damage involved. Unfortunately, the feeding activities of wildlife and the interests of the land managers are often in conflict. Few realize the breadth, scope, and subtilities associated with forest wildlife damage problems. There are not only numerous species of animals involved, but also a myriad of conditions, each combination possessing unique facets. It is a foregone conclusion that an understanding of the conditions is essential to facilitate a solution to any given problem. Though there are numerous methods of reducing animal damage, all of which have application under some situations, in this discussion emphasis will be placed on the role of chemicals and on western problems. Because of the broadness and complexity of the problem, generalizing is necessary and only brief coverage will be possible. However, an attempt will be made to discuss the use and limitations of various control methods.

"IF YOU BUILD THEM UP, THEY WILL STAY": THE ROLE OF RECOGNITION AND FEEDBACK ON STUDENT RETENTION

While such stratagems are certainly well founded, and have achieved varying degrees of success, it may be that a more fundamentally vital area of examination is being largely overlooked, namely the impact of the high school experience.